Suppose a particle moves along a straight line with velocity v(t)=t2e−2tv(t)=t2e−2t meters per second after t seconds. How many meters has it traveled during the first t seconds?

Respuesta :

Explanation:

It is given that,

Velocity of the particle moving in straight line is :

[tex]v(t)=t^2e^{-2t}\ m/s[/tex]

We need to find the distance (x)  traveled by the particle during the first t seconds. It is given by :

[tex]x=\int\limits {v.dt}[/tex]

[tex]x=\int\limits {t^2e^{-2t}dt}[/tex]

Using by parts integration, we get the value of x as :

[tex]x=\dfrac{-(2t^2+2t+1)e^{-2t}}{4}\ meters[/tex]

Hence, this is the required solution.

For a particle moving along a straight line with a velocity [tex]v(t) = t^2e^-2t[/tex] the distance traveled in meters is [tex]\frac{e^-2t}{2} [t^2 - t + 1] + C[/tex]

Let us recall that;

v = ds/dt hence;

s = [tex]\int\limits^a_b {v} \, dt[/tex]

Within the first t seconds;

s = [tex]\int\limits^t_0 {v} \, dt[/tex]

Hence, for [tex]v(t)=t^2e^-2t[/tex]

s = [tex]\int\limits^t_0{t^2e^-2t } \, dt[/tex]

Integrating by parts;

[tex]\int\limits^t_0 {u\frac{dv}{dt} } \, dt = uv - \int\limits^t_0 {v\frac{du}{dt} } \, dt[/tex]

Note that;

u = [tex]t^2[/tex]

du = [tex]2tdt[/tex]

dv = [tex]e^-2tdt[/tex]

v = [tex]\frac{e^{-2t}}{-2}[/tex]

Substituting;

[tex]\int\limits^t_0 {t^2e^{-2t} } \, dt = t^2 (e^-2t/-2) - \int\limits^t_0 {(e^-2t/-2)} \, 2tdt[/tex]

Integrating by parts, we have the result;

[tex]\frac{e^-2t}{2} [t^2 - t + 1] + C[/tex]meters

Learn more: https://brainly.com/question/10038290

Q&A Education